The invention relates to a novel process for the preparation of an enantiomerically pure 7-amino-5H,7H-dibenzo[b,d]azepin-6-one. The (S)-7-amino-5H,7H-dibenzo[b,d]azepin-6-one enantiomer can be used as a chiral building block for the preparation of malonamide derivatives which have the potential to act as γ-secretase inhibitors and therefore may be useful in the treatment of Alzheimer's disease and cancer.
The preparation of enantiomerically pure 7-amino-5H,7H-dibenzo[b,d]azepin-6-one has been accomplished using HPLC over a chiral stationary phase. However, such methods are suitable at laboratory scale only. The object of the present invention, therefore, is the production of chiral 7-amino-5H,7H-dibenzo[b,d]azepin-6-one with high enantiomeric excess and with a process which is applicable on a technical scale.